Narrative:

At or near XA30 on feb/tue/2000, I was practicing low altitude simulated engine failures in a bellanca 8KCAB decathlon, over the southwest corner of rosamond dry lake near mojave, ca. My practice placed me at and below 500 ft AGL. While practicing, I encountered a flight of 4 blackhawk helicopters moving southeast to northwest over my position at approximately 500 ft AGL and 2000 ft horizontal distance from my airplane. 2 of the blackhawks appeared to make an altitude change in order to avoid my airplane. They passed over my airplane about 200 ft higher. Narrative: at the time, I was in a class G airspace over the southern boundary of isabella and buckhorn MOA's, northeast of general fox airport at 035 degrees magnetic and 8 NM, nnw of lancaster airport at 340 degrees and 12 NM, and southwest of edwards air force base 220 degrees and 12 NM. I chose the area as a practice area because it is in uncontrolled airspace, because it is unpopulated and free of persons, vessels, vehicles and structures, because rosamond lake's southwest corner served as an excellent landmark for keeping me clear of restr area R-2515, because the area I selected was flat and clear of obstructions in all directions, and because the dry lake bed provided a safe landing area in the unlikely event of an engine failure at low altitude. In order to maintain visual contact with the helicopters, I made a 270 degree turn to the left. I made use of the 'greenhouse' overhead panel in the decathlon I was flying to keep the helicopters above me in sight. After the helicopters passed overhead, I terminated my low altitude practice and headed to mojave airport. I flew on a n-northwesterly course towards the west flank of silver queen mountain in preparation for a VFR entry into the pattern at mojave. My course put me 1-2 mi in trail of the helicopters. I believed my airspeed of 90 KTS was well below that of the helicopters. I also felt I was at a safe distance behind the rearmost of the 4 helicopters. Approximately 3 mi northwest of rosamond, 2 of the helicopters broke out of formation to the east and circled around to my 6 O'clock position, above and behind my airplane. The other 2 helicopters continued nnwbound. I was extremely uncomfortable being sandwiched between 2 helicopters ahead and 2 behind. Moreover, I was unable to maintain visual contact with the helicopters behind me despite repeated attempts to slip my airplane for a better view to the rear through the side windows (the decathlon has no rear window). In order to keep an eye on the helicopters, I made a 360 degree turn to the left and placed myself once again behind the helicopters. As soon as I was again in trail of all 4 helicopters, the 2 rearmost helicopters of the flight made a 360 degree turn to the right and repositioned themselves high and behind my airplane. I gave up trying to circle back behind the helicopters and continued on to mojave. While en route to mojave, I climbed to traffic pattern altitude of 1000 ft AGL. During the climb, I attempted to slip my airplane to keep the trailing helicopters in sight. I was extremely concerned about not being able to see the helicopters behind me. I was so preoccupied that I may have flown within 500 ft of a structure before I was able to climb to 1000 ft AGL. I contacted mojave tower and he advised me to be cautious of 2 helicopters that had entered the mojave class D surface area without contacting the tower. I responded that I was already aware of the helicopters and that, in fact, there was 4, 2 of which were behind me not yet visible to the tower controller. I made an uneventful landing at mojave after entering a right downwind for runway 12.

Google
 

Original NASA ASRS Text

Title: A BELLANCA DECATHLON PLT RPT ON AN NMAC WITH A FORMATION FLT OF BLACKHAWK HELIS 8 MI NE OF WJF, CA.

Narrative: AT OR NEAR XA30 ON FEB/TUE/2000, I WAS PRACTICING LOW ALT SIMULATED ENG FAILURES IN A BELLANCA 8KCAB DECATHLON, OVER THE SW CORNER OF ROSAMOND DRY LAKE NEAR MOJAVE, CA. MY PRACTICE PLACED ME AT AND BELOW 500 FT AGL. WHILE PRACTICING, I ENCOUNTERED A FLT OF 4 BLACKHAWK HELIS MOVING SE TO NW OVER MY POS AT APPROX 500 FT AGL AND 2000 FT HORIZ DISTANCE FROM MY AIRPLANE. 2 OF THE BLACKHAWKS APPEARED TO MAKE AN ALT CHANGE IN ORDER TO AVOID MY AIRPLANE. THEY PASSED OVER MY AIRPLANE ABOUT 200 FT HIGHER. NARRATIVE: AT THE TIME, I WAS IN A CLASS G AIRSPACE OVER THE SOUTHERN BOUNDARY OF ISABELLA AND BUCKHORN MOA'S, NE OF GENERAL FOX ARPT AT 035 DEGS MAGNETIC AND 8 NM, NNW OF LANCASTER ARPT AT 340 DEGS AND 12 NM, AND SW OF EDWARDS AIR FORCE BASE 220 DEGS AND 12 NM. I CHOSE THE AREA AS A PRACTICE AREA BECAUSE IT IS IN UNCTLED AIRSPACE, BECAUSE IT IS UNPOPULATED AND FREE OF PERSONS, VESSELS, VEHICLES AND STRUCTURES, BECAUSE ROSAMOND LAKE'S SW CORNER SERVED AS AN EXCELLENT LANDMARK FOR KEEPING ME CLR OF RESTR AREA R-2515, BECAUSE THE AREA I SELECTED WAS FLAT AND CLR OF OBSTRUCTIONS IN ALL DIRECTIONS, AND BECAUSE THE DRY LAKE BED PROVIDED A SAFE LNDG AREA IN THE UNLIKELY EVENT OF AN ENG FAILURE AT LOW ALT. IN ORDER TO MAINTAIN VISUAL CONTACT WITH THE HELIS, I MADE A 270 DEG TURN TO THE L. I MADE USE OF THE 'GREENHOUSE' OVERHEAD PANEL IN THE DECATHLON I WAS FLYING TO KEEP THE HELIS ABOVE ME IN SIGHT. AFTER THE HELIS PASSED OVERHEAD, I TERMINATED MY LOW ALT PRACTICE AND HEADED TO MOJAVE ARPT. I FLEW ON A N-NORTHWESTERLY COURSE TOWARDS THE W FLANK OF SILVER QUEEN MOUNTAIN IN PREPARATION FOR A VFR ENTRY INTO THE PATTERN AT MOJAVE. MY COURSE PUT ME 1-2 MI IN TRAIL OF THE HELIS. I BELIEVED MY AIRSPD OF 90 KTS WAS WELL BELOW THAT OF THE HELIS. I ALSO FELT I WAS AT A SAFE DISTANCE BEHIND THE REARMOST OF THE 4 HELIS. APPROX 3 MI NW OF ROSAMOND, 2 OF THE HELIS BROKE OUT OF FORMATION TO THE E AND CIRCLED AROUND TO MY 6 O'CLOCK POS, ABOVE AND BEHIND MY AIRPLANE. THE OTHER 2 HELIS CONTINUED NNWBOUND. I WAS EXTREMELY UNCOMFORTABLE BEING SANDWICHED BTWN 2 HELIS AHEAD AND 2 BEHIND. MOREOVER, I WAS UNABLE TO MAINTAIN VISUAL CONTACT WITH THE HELIS BEHIND ME DESPITE REPEATED ATTEMPTS TO SLIP MY AIRPLANE FOR A BETTER VIEW TO THE REAR THROUGH THE SIDE WINDOWS (THE DECATHLON HAS NO REAR WINDOW). IN ORDER TO KEEP AN EYE ON THE HELIS, I MADE A 360 DEG TURN TO THE L AND PLACED MYSELF ONCE AGAIN BEHIND THE HELIS. AS SOON AS I WAS AGAIN IN TRAIL OF ALL 4 HELIS, THE 2 REARMOST HELIS OF THE FLT MADE A 360 DEG TURN TO THE R AND REPOSITIONED THEMSELVES HIGH AND BEHIND MY AIRPLANE. I GAVE UP TRYING TO CIRCLE BACK BEHIND THE HELIS AND CONTINUED ON TO MOJAVE. WHILE ENRTE TO MOJAVE, I CLBED TO TFC PATTERN ALT OF 1000 FT AGL. DURING THE CLB, I ATTEMPTED TO SLIP MY AIRPLANE TO KEEP THE TRAILING HELIS IN SIGHT. I WAS EXTREMELY CONCERNED ABOUT NOT BEING ABLE TO SEE THE HELIS BEHIND ME. I WAS SO PREOCCUPIED THAT I MAY HAVE FLOWN WITHIN 500 FT OF A STRUCTURE BEFORE I WAS ABLE TO CLB TO 1000 FT AGL. I CONTACTED MOJAVE TWR AND HE ADVISED ME TO BE CAUTIOUS OF 2 HELIS THAT HAD ENTERED THE MOJAVE CLASS D SURFACE AREA WITHOUT CONTACTING THE TWR. I RESPONDED THAT I WAS ALREADY AWARE OF THE HELIS AND THAT, IN FACT, THERE WAS 4, 2 OF WHICH WERE BEHIND ME NOT YET VISIBLE TO THE TWR CTLR. I MADE AN UNEVENTFUL LNDG AT MOJAVE AFTER ENTERING A R DOWNWIND FOR RWY 12.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.